Active matrix substrate and display panel

ABSTRACT

An array board 11b includes a display section AA, a source line 20 connected to the display section AA, a test circuit 40 connected to the source line 20 and configured to test the display section AA, a panel-side image input terminal that is disposed such that the test circuit 40 is between the terminal and the display section AA and to which a signal to be supplied to the source line 20 is input, a terminal connection line 51 connecting the source line 20 to the pane-side image input terminal 35A and the terminal connection line 51 including the terminal connection line 51 at least a part of which overlaps the test circuit 40 and a flattening film (insulation film) 28 at least disposed between an overlapping portion of the test circuit 40 and the terminal connection line 51.

TECHNICAL FIELD

The present invention relates to an active matrix substrate and adisplay panel.

BACKGROUND ART

Examples of known display devices are described in Patent Documents 1and 2. Patent Document 1 describes a display device including aswitching element for video signal selection which selectively connectsan arbitrary source line to one of a plurality of video signal supplylines, a scan signal selection element which selectively connects anarbitrary gate line to one of a plurality of scan signal supply lines, aplurality of external signal connection terminals, and a plurality ofinspection terminals. Inspection switching elements are connected toeach of the plurality of video signal supply lines, and the plurality ofinspection switching elements have input terminal sides connected inparallel and connected to a first inspection terminal and have controlterminal sides connected in parallel and connected to a secondinspection terminal, and a plurality of color selection signal supplylines are connected to a plurality of third inspection terminals, andthe plurality of scan signal supply lines are connected to a pluralityof fourth inspection terminals.

Patent Document 2 describes a following display device. A halfwaysection of a video signal wiring group lead out of a source driverbetween its routing position and an external connection terminalcorresponding to the driver is separated, and the separated video signalwiring group is arranged as a bypass wiring group on a surface of acounter electrode substrate opposed to a liquid crystal layer. Bypasselectrodes at both ends of the bypass wiring group and bypass electrodesat two ends of remaining video signal wiring groups left by parting thevideo signal wiring group on an array board are connected in seriesthrough a conductive member buried in a seal material. Further, thesource driver on the array board and the corresponding bypass wiringgroup on the counter substrate are put one over the other along thewidth in plan view of the panel.

RELATED ART DOCUMENT Patent Document

-   Patent Document 1: Japanese Unexamined Patent Application    Publication No. 2010-243526-   Patent Document 1: Japanese Unexamined Patent Application    Publication No. 2007-264447

Problem to be Solved by the Invention

In the device described in Patent Document 1, in a peripheral sectionthat is around the display section including the pixel electrodes andthe TFTs, the signal selection circuit such as the switching element forvideo signal selection, the inspection circuit such as inspectionswitching elements, the routing lines connected to the source line, andthe driver IC mounting terminal connected to the routing lines arearranged so as not to overlap each other. According to such aconfiguration, a frame area of the array board tends to be large andthis may be a problem for achieving high display resolution.

In the device described in Patent Document 2, a part of the routingwiring group connecting the external connection terminal and the sourcedriver is arranged as the bypass wiring group on a counter electrodesubstrate side opposed to the array board to reduce the frame area.However, with such a method, plane arrangement of the routing wiringgroup is limited and the routing wiring group has poor arrangementvariety. Further, if the bypass wiring group on the counter electrodesubstrate side overlaps the circuit on the array board side, such aconfiguration is likely to be influenced by noise and measure againstnoise such as providing shield electrodes may be necessary.

DISCLOSURE OF THE PRESENT INVENTION

An object of the present invention is to reduce a frame area and keepvariety of arrangement and receive less influence of noise.

Means for Solving the Problem

An active matrix substrate according to the present invention includes apixel section, a pixel connection line connected to the pixel section, atest circuit connected to the pixel connection line and configured totest the pixel section, a terminal that is disposed such that the testcircuit is present between the terminal and the pixel section and towhich a signal to be supplied to the pixel connection line is input, aterminal connection line connecting the pixel connection line to theterminal, at least a part of the terminal connection line overlappingthe test circuit, and an insulation film at least disposed between anoverlapping portion of the test circuit and the terminal connectionline.

The signals input to the terminal are sequentially transmitted to theterminal connection line and the pixel connection line and supplied tothe pixel section. The pixel section is driven based on the suppliedsignals. In testing the pixel section during the manufacturing process,the test signals are supplied from the test circuit to the pixel sectionvia the pixel connection line. The pixel section is driven based on thesupplied test signals. The terminal connection line is connected to theterminal via the terminal connection line, and the test circuit isbetween the pixel section and the terminal. At least a part of eachterminal connection line overlaps the test circuit via the insulationfilm. With such a configuration, compared to a configuration that theterminal connection line does not overlap the test circuit, the area forthe terminal connection line and the test circuit is reduced.Accordingly, the frame area of the active matrix substrate can bereduced and display resolution can be preferably enhanced. Further, thearrangement variety of the terminal connection line and the test circuitcan be increased. The test circuit is not used when the signals areinput to the terminal. Therefore, the signals transmitted to theterminal connection line are not adversely affected by the noise evenwith the configuration that the test circuit overlaps the terminalconnection line via the insulation film, and signal delay is less likelyto be caused.

Following configurations may be preferable for embodiments of thepresent technology.

(1) The terminal may be positioned off from the pixel connection linewith respect to a direction perpendicular to an extending direction inwhich the pixel connection line extends, and the terminal connectionline may include an obliquely extending portion that extends obliquelywith respect to the extending direction of the pixel connection line andthe obliquely extending portion may overlap the test circuit. Accordingto such a configuration, the obliquely extending portion is arrangedwith using an arrangement area of the test circuit, and a frame area canbe reduced.

(2) The pixel section may include pixels that are arranged in a matrixand the pixel connection line may include multiple pixel connectionlines that are connected to the pixels, respectively, the test circuitmay at least include a test line extending in a direction crossing anextending direction in which the pixel connection line extends andthrough which test signals are transmitted, and a test switchingcomponent that is connected to the test line and the pixel connectionline and configured to control supply of the test signals, and the testline may include test lines that are connected to the pixel connectionlines connected to odd-numbered pixels of the pixels from an end in theextending direction of the test line and test lines that are connectedto the pixel connection lines connected to even-numbered pixels of thepixels from the end. According to such a configuration, it can be testedwith the test circuit whether short-circuit is caused between theodd-numbered pixels and pixel connection lines from the end with respectto the extending direction of the test line and the even-numbered pixelsand pixel connection lines. Compared to a configuration including threeor more test lines, the area for the test circuit can be smaller and aframe area can be preferably reduced.

(3) The pixel section may include coloring pixels of multiple colorsthat exhibit different colors and the pixel connection line may includemultiple pixel connection lines connected to the coloring pixels ofmultiple colors, the test circuit may at least include a test linethrough which test signals are transmitted, and a test switchingcomponent that is connected to the test line and the multiple pixelconnection lines and configured to control supply of the test signals,and the test line may include multiple test lines that are connected tothe multiple pixel connection lines, respectively, and a number of themultiple test lines may be equal to a number of the multiple colors ofthe coloring pixels. According to such a configuration, with the testcircuit, the single color display may be performed by drivingselectively each of the single coloring pixels of multiple colors or themixed color display may be performed by driving simultaneously themultiple coloring pixels of the multiple colors. Accordingly, varioustests can be performed. In such a configuration including the samenumber of test lines as the number of colors of the coloring pixels, thearrangement area of the test circuit may be increased. However, asdescribed before, the terminal connection line is arranged whileoverlapping the test circuit and therefore, the arrangement efficiencyof the terminal connection line and the test circuit is improved and theframe area can be kept small.

(4) The pixel section may include coloring pixels of multiple colorsthat exhibit different colors and the pixel connection line may includemultiple pixel connection lines connected to the coloring pixels ofmultiple colors, the active matrix substrate may further include aswitching circuit arranged between the pixel section and the testcircuit and connected to the respective multiple pixel connection linesand configured to supply signals selectively to the respective multiplepixel connection lines, and the terminal connection line may beconnected to the pixel connection line via the switching circuit.According to such a configuration, with the switching circuit, thecoloring pixels of each color can be selectively driven at certaingradation by supplying signals selectively to the pixel connectionlines. In a configuration including such a switching circuit, the framearea may be increased by the arrangement area of the switching circuit.However, since the number of the terminal connection lines is greatlydecreased and the terminal connection line is arranged while overlappingthe test circuit as described before, the arrangement efficiency of theterminal connection line and the test circuit is improved and the framearea can be kept small.

(5) The pixel section may include pixels arranged in a matrix, thepixels may include pixel electrodes to which a potential according to asupplied signal is applied, and a common electrode to which a commonpotential is applied, the common electrode may include separated commonelectrodes that are arranged in a matrix and in an area ranging thepixel electrodes, the pixel connection line may include multiple pixelelectrode pixel connection lines connected to the pixel electrodes andmultiple common electrode pixel connection lines connected to therespective separated common electrodes, and the terminal connection linemay include at least terminal connection lines connected to the pixelelectrode pixel connection lines or terminal connection lines connectedto the common electrode pixel connection lines. According to such aconfiguration, the pixel electrodes are supplied with a potentialaccording to the signal supplied via the pixel electrode pixelconnection lines, and the separated common electrodes included in thecommon electrodes are supplied with a common potential supplied via thecommon electrode pixel connection lines. Display with gradationaccording to the potential difference between each pixel electrode andthe common electrode is performed in each pixel. In a configuration thatthe terminal connection lines including terminal connection linesconnected to the pixel electrode pixel connection lines, signalssupplied to the terminal are transmitted to the pixel electrode pixelconnection lines via the terminal connection lines overlapping the testcircuit. In a configuration that the terminal connection lines includingterminal connection lines connected to the common electrode pixelconnection lines, the common potential suppled to the terminals istransmitted to the common electrode pixel connection lines via theterminal connection lines that overlap the test circuit.

(6) The terminal connection lines may selectively include the terminalconnection lines connected to the common electrode pixel connectionlines, the test circuit may be connected to the pixel electrode pixelconnection lines and configured to test the pixel electrode pixelconnection lines, and the active matrix substrate may further include asecond test circuit arranged between the test circuit and the pixelsection and configured to test the common electrode pixel connectionlines, and the terminal connection lines connected to the commonelectrode pixel connection lines may be arranged while overlapping thesecond test circuit in addition to the test circuit via the insulationfilm. According to such a configuration, it can be tested with thesecond test circuit whether short-circuit is caused between the adjacentseparated common electrodes and it can be tested with the test circuitwhether short-circuit is caused between the adjacent pixel electrodes.In such a configuration including the second test circuit, the framearea may be increased by the arrangement area for the second testcircuit. However, the terminal connection lines are disposed whileoverlapping the test circuit and the second test circuit so that thearrangement efficiency of the terminal connection lines, the testcircuit, and the second test circuit is improved and the frame area canbe kept small.

Next, to solve the above problem, a display panel according to thepresent technology includes the above-described active matrix substrate,and a counter board bonded to the active matrix substrate. According tothe display panel having such a configuration, the active matrixsubstrate has a reduced frame area and a design property of the displaypanel is improved.

Advantageous Effect of the Invention

According to the present invention, a frame area is reduced and varietyof arrangement is kept and less influence of noise is received.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a general plan view illustrating a connection structure of aliquid crystal panel including a driver, a flexible printed circuitboard, and a control circuit board according to a first embodiment ofthe present invention.

FIG. 2 is a general cross-sectional view illustrating a cross-sectionalconfiguration of a liquid crystal display device taken along a long-sidedirection thereof.

FIG. 3 is a general cross-sectional view illustrating a cross-sectionalconfiguration of a display part of the liquid crystal panel.

FIG. 4 is a general plan view illustrating a trace structure in adisplay section of an array board of the liquid crystal panel.

FIG. 5 is an enlarged plan view illustrating a planar configuration ofthe display section of a CF board of the liquid crystal panel.

FIG. 6 is a cross-sectional view of the array board of the liquidcrystal panel taken along line A-A in FIG. 4.

FIG. 7 is a plan view illustrating a configuration of traces in amounting area of the array board where the driver and the flexibleprinted circuit board are mounted.

FIG. 8 is a cross-sectional view illustrating the driver and the arrayboard taken along Y-axis direction.

FIG. 9 is an enlarged plan view illustrating a section near a testcircuit in FIG. 7.

FIG. 10 is a cross-sectional view illustrating a cross-sectionalconfiguration of a test TFT of the array board.

FIG. 11 is a cross-sectional view taken along line B-B in FIG. 9.

FIG. 12 is a cross-sectional view taken along line C-C in FIG. 9.

FIG. 13 is a plan view illustrating a configuration of traces in amounting area of an array board where the driver and the flexibleprinted circuit board are mounted according to a second embodiment ofthe present invention.

FIG. 14 is a plan view illustrating a configuration of traces in amounting area of an array board where the driver and the flexibleprinted circuit board are mounted according to a third embodiment of thepresent invention.

FIG. 15 is a general plan view illustrating a configuration of a commonelectrode and a test circuit in an array board according to a fourthembodiment of the present invention.

FIG. 16 is a plan view illustrating a configuration of traces in amounting area of an array board where the driver and the flexibleprinted circuit board are mounted.

MODES FOR CARRYING OUT THE INVENTION First Embodiment

A first embodiment of the present technology will be described withreference to FIGS. 1 to 12. In this embodiment, a liquid crystal displaydevice 10 will be described as an example. X-axis, Y-axis and Z-axis maybe present in the drawings and each of the axial directions represents adirection represented in each drawing. A vertical direction is referredto FIG. 2 and an upper side and a lower side in FIG. 2 correspond to afront side and a back side, respectively.

As illustrated in FIGS. 1 and 2, the liquid crystal display device 10includes a liquid crystal panel (display panel) 11, a driver (a pixeldriving section) 21 driving the liquid crystal panel 11, a controlcircuit board (an external signal supply source) 12 supplying variouskinds of input signals from outside to the liquid crystal panel 11including the driver 21, the flexible printed circuit board (an externalconnection part) 13 electrically connecting the liquid crystal panel 11and the external control circuit board 12, a backlight unit (a lightingdevice) 14 that is an external light source supplying light to theliquid crystal panel 11. The liquid crystal display device 10 furtherincludes a pair of front and rear exterior members 15, 16 to hold theliquid crystal panel 11 and the backlight unit 14 that are attachedtogether. The front exterior member 15 has an opening hole 15 a throughwhich images displayed on the liquid crystal panel 11 can be seen fromthe outside.

Next, a configuration of the backlight unit 14 will be brieflydescribed. As illustrated in FIG. 2, the backlight unit 14 includes achassis 14 a that has a substantially box shape opening toward the frontside (toward the liquid crystal panel 11), a light source (such as coldcathode tubes, LEDs, organic EL, not illustrated) not illustrated andarranged within the chassis 14 a, and an optical member (notillustrated) arranged to cover an opening hole of the chassis 14 a. Theoptical member is configured to convert light rays from the light sourceinto planar light.

The liquid crystal panel 11 will be described. As illustrated in FIG. 1,the liquid crystal panel 11 has a vertically-long square (rectangular)shape as a whole. The liquid crystal panel 11 includes a display section(a pixel section, an active area, a display area) AA that is offcentered toward one of ends of a short dimension thereof (the upper sidein FIG. 1). The driver 21 and the flexible printed circuit board 13 arearranged at the other end of the short dimension of the liquid crystalpanel 11 (the lower side in FIG. 1). An area of the liquid crystal paneloutside the display section AA is a non-display section (non-activearea, a non-display area) NAA in which images are not displayed. Ashort-side direction and a long-side direction of the liquid crystalpanel 11 correspond to the X-axis direction and the Y-axis direction ineach drawing. In FIGS. 1 and 7, a dot-and-dash line box slightly smallerthan a CF board 11 a indicates an outline of the display section AA. Anarea outside the dot-and-dash line is the non-display section NAA.

As illustrated in FIG. 3, the liquid crystal panel includes a pair oftransparent substrates (having high transmissivity) 11 a and 11 b, and aliquid crystal layer 11 c between the substrates 11 a and 11 b. Theliquid crystal layer 11 c includes liquid crystal molecules havingoptical characteristics that vary according to application of electricfield. The substrates 11 a and 11 b are bonded together with a sealingagent, which is not illustrated, with a gap therebetween. The substrates11 a, 11 b include a CF board (a counter board) 11 a on the front and anarray board (an active matrix substrate, a component substrate) 11 b ona back side. As illustrated in FIGS. 1 and 2, the CF board 11 a has ashort-side dimension that is substantially equal to that of the arrayboard 11 b and has a long-side dimension smaller than that of the arrayboard 11 b. The CF board 11 a is bonded to the array board 11 b suchthat one of the short-side edges (an upper side in FIG. 1) of each ofthe substrates is aligned with each other. Accordingly, edge portion ofthe array board 11 b on another one of the short-side edges (a lowerside in FIG. 1) does not overlap the CF board 11 a over a certain areaand front and rear plate surfaces thereof are exposed outside. Such acertain area of the array board is a mounting area for the driver 21 andthe flexible printed circuit board 13 (an arrangement area of terminals33-35). Alignment films 11 d and 11 e are formed on inner surfaces ofthe substrates 11 a and 11 b, respectively, for aligning the liquidcrystal molecules included in the liquid crystal layer 11 c. Polarizingplates 11 f and 11 g are bonded to outer surfaces of the substrates 11 aand 11 b, respectively.

Next, configurations of the array board 11 b and the CF board 11 a inthe display section AA will be described. As illustrated in FIGS. 3 and4, a number of pixel TFTs (thin film transistors) 17 that are switchingcomponents (display components) and a number of pixel electrodes 18 arearranged in a matrix on the inner surface of the array board 11 b (theliquid crystal layer 11 c side, the opposed surface side opposed to theCF board 11 a). Furthermore, the gate lines (row control lines, scanlines) 19 and the source lines (pixel connection lines, column controllines, data lines) 20 are arranged in a grid to surround the pixel TFTs17 and the pixel electrodes 18. Namely, the pixel TFTs 17 and the pixelelectrodes 18 are arranged at the respective intersections of the gatelines 19 and the source lines 20 in a grid. The pixel TFTs 17 and thepixel electrodes 18 are arranged in a matrix in rows and columns (theX-axis direction and the Y-axis direction). A common electrode 32 isdisposed on the array board 11 b and an electric field is formed betweenthe common electrode 32 and the pixel electrode 18 according to thesupply of a common potential (a reference potential). In thisembodiment, a driving type of the liquid crystal panel 11 is a fringefiled switching (FFS) type that is a mode improved from an in-planeswitching (IPS) mode. The pixel electrodes 18 and the common electrode32 are formed on the array board 11 b side and the pixel electrodes 18and the common electrode 32 are included in different layers. The pixelelectrode 18 has slits 18 a that are arranged at intervals and each ofwhich extends obliquely with respect to the X-axis direction and theY-axis direction in the plan view. If potential difference is generatedthrough the slits 18 a between the pixel electrode 18 and the commonelectrode 32 that is included in different layers, a fringe field (anoblique field) including a component in a direction normal to a platesurface of the array board 11 b is applied to the liquid crystal layerin addition to a component in a direction along the plate surface of thearray board 11 b. The alignment state of the liquid crystal moleculesincluded in the liquid crystal layer 11 c can be switched appropriatelywith using the fringe filed.

As illustrated in FIGS. 3 and 5, color filters 11 h are formed on the CFboard 11 a. The color filters 11 h include red (R), green (G), and blue(B) color portions that are arranged in a matrix and in rows (the X-axisdirection) and columns (the Y-axis direction) to overlap the pixelelectrodes 18 on the array board 11 b in a plan view. A light blockinglayer 11 i having a grid shape (a black matrix) is formed between thecolor portions included in the color filters 11 h for reducing colormixture. The light blocking layer 11 i is arranged while overlapping thegate lines 19 and the source lines 20 in a plan view. An overcoat film(a flattening film) 11 j is formed on inner surfaces of the colorfilters 11 h and the light blocking layer 11 i.

Next, the various films formed in layers on the inner surface side ofthe array board 11 b with the known photolithography method will bedescribed. A specific layering order of the films will be described.Components fora function of displaying images (displaying function)among functions of the liquid crystal panel 11 are mainly included inthe array board lib. As illustrated in FIG. 6, on the array board lib,the following films are at least formed in the following sequence fromthe lowest layer (the glass substrate GS side, a rear side): a basecoatfilm 22, a semiconductor film 23, a gate insulation film (an insulationfilm) 24, a first metal film (a gate metal film) 25, a first interlayerinsulation film (an inorganic insulation film) 26, a second metal film(a source metal film) 27, a flattening film (an organic insulation film)28, a first transparent electrode film 29, a second interlayerinsulation film (an inorganic insulation film) 30, and a secondtransparent electrode film 31 are at least formed in layers. As is notillustrated, the alignment film 11 e is included in an upper layer ofthe second interlayer insulation film 30 and the second transparentelectrode film 31. An insulation film 52 is disposed on the flatteningfilm 28 such that a third metal film 53, which will be described layer,is insulated from other conductive films. The third metal film 53 isbetween the flattening film 28 and the insulation film 52.

The basecoat film 22 is provided in a solid pattern covering an entiresurface of the glass substrate GS of the array board lib, and is made ofsilicon oxide (SiO₂), silicon nitride (SiNx), or silicon nitrified oxide(SiON). As illustrated in FIG. 6, the semiconductor film 23 is disposedon an upper layer side of the basecoat film 22 and formed withpatterning in the display section AA and the non-display section NAA.The semiconductor film 23 is formed with patterning in an island formaccording to the arrangement of the pixel TFTs 19 in at least thedisplay section AA. The semiconductor film 23 is made of a continuousgrain (CG) silicon thin film that is a kind of a polycrystallizedsilicon film (a polycrystalline silicone film). The CG silicon film isformed as follows. Metal material is added to an amorphous silicon thinfilm and the additive is subjected to a heating process at a lowtemperature of 550° C. or lower fora short time. Accordingly, atomicarrangement at a crystal grain boundary of the silicon crystals hascontinuity. The gate insulation film 24 is arranged on an upper layerside of the basecoat film 22 and the semiconductor film 23 and formed ina solid pattern in an area ranging over the display section AA and thenon-display section NAA. For example, the gate insulation film 24 ismade of SiO₂.

As illustrated in FIG. 6, the first metal film 25 is arranged on anupper layer side of the gate insulation film 24 and disposed in each ofthe display section AA and the non-display section NAA with patterning.The first metal film 25 is made of metal material having a high meltingpoint and large sheet resistance such as tantalum (Ta) or tungsten (W).The gate lines 19 are formed of the first metal film 25. The firstinterlayer insulation film 26 is arranged on an upper layer side of thegate insulation film 24 and the first metal film 25 and is formed in asolid pattern disposed in an area ranging over the display section AAand the non-display section NAA. The first interlayer insulation film 26is made of silicon oxide (SiO₂). The insulation between the crossingportions of the gate lines 19 and the source lines 20 is maintained bythe first interlayer insulation film 26. The second metal film 27 isarranged on an upper layer side of the first interlayer insulation film26 and is disposed in each of the display section AA and the non-displaysection NAA with patterning. The second metal film 27 is made of metalmaterial that is easily corrosive and has small sheet resistance such asaluminum (Al) or chromium copper (Cr). The source lines 20 and othercomponents are formed of the second metal film 27. The flattening film28 that is an insulation film is arranged on an upper layer side of thefirst interlayer insulation film 26 and the second metal film 27 and isformed in a solid pattern disposed in an area ranging over the displaysection AA and the non-display section NAA. The flattening film 28 ismade of acrylic resin such as polymethyl methacrylate resin (PMMA). Theflattening film 28 has a film thickness relatively greater than those ofthe insulation films 24, 26, 30 that are inorganic insulation films.Therefore, the surface of the array board 11 b facing the liquid crystallayer 11 c (on which the alignment film is disposed) can be effectivelyflattened by the flattening film 28. In a configuration including thelines made of the third metal film 53, a capacitance composition isgenerated in a section where the lines overlap the lines made of thefirst metal film 25 or the second metal film 27. However, the flatteningfilm 28 that is relatively thick can reduce a load caused by thecapacitance composition. The third metal film 53 can be disposed on anyother conductive film as long as having an insulation film therebetween.However, the third metal film 53 is preferably disposed on theflattening film 28 due to the above reason.

As illustrated in FIG. 6, the first transparent electrode film 29 isarranged on an upper layer side of the flattening film 28 and formed ina substantially solid pattern at least in the display section AA. Thefirst transparent electrode film 29 is made of transparent electrodematerial such as indium tin oxide (ITO) or zinc oxide (ZnO). The commonelectrode 32 that is formed in a substantially solid pattern is formedof the first transparent electrode film 29. The second interlayerinsulation film 30 is arranged on an upper layer side of the flatteningfilm 28 and the first transparent electrode film 29 and formed in asolid pattern in an area ranging the display section AA and thenon-display section NAA. The second interlayer insulation film 30 ismade of silicon nitride (SiN_(x)). The second transparent electrode film31 is arranged on an upper layer side of the second interlayerinsulation film 30 and formed in an island form in the display sectionAA with patterning according to the arrangement of the pixel TFTs 17.The second transparent electrode film 31 is made of transparentelectrode material similar to that of the first transparent electrodefilm 29. The pixel electrodes 18 are formed of the second transparentelectrode film 31. Holes such as contact holes CH1, CH2 are formed atcertain positions in the gate insulation film 24, the first interlayerinsulation film 26, the flattening film 28, and the second interlayerinsulation film 30 with patterning in the process of producing the arrayboard 11 b.

The pixel TFT 17 disposed in the display section AA of the array board11 b is a so-called top-gate type (a staggered type) TFT. As illustratedin FIG. 6, such a pixel TFT 17 includes a channel portion 17 d formed ofthe semiconductor film 23, the gate electrode 17 a, the source electrode17 b, and the drain electrode 17 c. The gate electrode 17 a is disposedto overlap the channel portion 17 d on an upper layer side while havingthe gate insulation film 24 therebetween. The source electrode 17 b andthe drain electrode 17 c are disposed on an upper layer side of the gateelectrode 17 a via the first interlayer insulation film 26. The gateelectrode 17 a is made of the first metal film 25, and the sourceelectrode 17 b and the drain electrode 17 c are made of the second metalfilm 27. Among them, the source electrode 17 b and the drain electrode17 c are connected to the channel portion 17 d through the contact holeCH1 that is formed in the gate insulation film 24 and the firstinterlayer insulation film 26. Accordingly, electrons move between thesource electrode 17 b and the drain electrode 17 c. The semiconductorfilm 23 of the channel portion 17 d is made of the CG silicon thin film,as described before. The CG silicon thin film has electron mobility of200 to 300 cm²/Vs, for example, that is higher than that of an amorphoussilicon film. The pixel TFT 17 including the semiconductor film 23 madeof the CG silicon thin film as the channel portion 17 d can be easilydownsized and an amount of transmitted light through each pixelelectrode 18 can be increased to a maximum level. This configuration ispreferable for enhancement of image resolution and reduction of powerconsumption. The pixel electrode 18 formed of the second transparentelectrode film 31 is connected to the drain electrode 17 c of the pixelTFT 17 through the contact hole CH2 formed in the flattening film 28 andthe second interlayer insulation film 30 and the insulation film 52,which will be described later. Accordingly, if power is supplied to thegate electrode 17 a of the pixel TFT 17, current flows between thesource electrode 17 b and the drain electrode 17 c via the channelportion 17 d and a certain potential is applied to the pixel electrode18. The common electrode 32 formed of the first transparent electrodefilm 29 overlaps the pixel electrodes 18 in a plan view and the commonelectrode 32 and the pixel electrodes 18 sandwich the second interlayerinsulation film 30 therebetween. The common electrode 32 that isdisposed in a solid pattern has holes in portions overlapping therespective contact holes CH2 of the flattening film 28 and the secondinterlayer insulation film 30. The contact portions of the pixelelectrodes 18 pass through the holes of the common electrode 32.

As illustrated in FIGS. 3 to 5, the pixel TFT 17, the pixel electrode 18and the common electrode 32 disposed on the array board 11 b form thepixel PX and the pixel PX is a coloring pixel that exhibits a colorcorresponding to the coloring portion of the color filter 11 h oppositethe pixel electrode 18 of the pixel PX. The pixels PX include a redpixel (the coloring pixel) RPX exhibiting red, a green pixel (thecoloring pixel) GPX exhibiting green, and a blue pixel (the coloringpixel) exhibiting blue. The three pixels form one display unit and thepixels are arranged in repeated sequence along the row direction (theX-axis direction) and the column direction (the Y-axis direction). Amongthe pixels PX arranged in rows and columns, the pixels PX arranged inthe row direction that are connected to the same gate line 19 form a rowof pixels and the pixels PX arranged in the column direction that areconnected to the same source line 20 form a column of pixels. Therefore,each pixel TFT 17 of the pixels PX included in a row of pixels isprovided with scan signals from the same gate line 19, and each pixelTFT 17 of the pixels PX included in a column of pixels is provided withimage signals (data signals, video signals) from the same source line20. Rows of pixels are arranged in the column direction and columns ofpixels are arranged in the row direction. Adjacent pixels PX included inthe row of pixels have different colors and adjacent pixels PX includedin the column of pixels have a same color.

Next, the components connected to the liquid crystal panel 11 will bedescribed. As illustrated in FIG. 2, the control circuit board 12 ismounted on the back surface of the chassis 14 a (an outer surface on aside opposite from the liquid crystal panel 11) of the backlight unit 14with screws. The control circuit board 12 includes a substrate made ofpaper phenol or glass epoxy resin and electronic components mounted onthe substrate and configured to supply various input signals to thedriver 21. Traces (electrically conductive paths) which are notillustrated are formed in predetermined patterns on the substrate. Anend (one end side) of the flexible printed circuit board 13 iselectrically and mechanically connected to the control circuit board 12via an anisotropic conductive film (ACF), which is not illustrated.

As illustrated in FIG. 2, the flexible printed circuit board (an FPCboard) 13 includes a base member made of synthetic resin havinginsulating property and flexibility (e.g., polyimide resin). A number oftraces are formed on the base member (not illustrated). The end of thelong dimension of the flexible printed circuit board 13 is connected tothe control circuit board 12 disposed on the back surface of the chassis14 a as described above. The other end (other end side) of the longdimension of the flexible printed circuit board 13 is connected to thearray board 11 b in the liquid crystal panel 11. The flexible printedcircuit board 13 is bent or folded back inside the liquid crystaldisplay device 10 such that a cross-sectional shape thereof forms aU-like shape. At the ends of the long dimension of the flexible printedcircuit board 13, portions of the traces are exposed to the outside andconfigured as terminals (not illustrated). The terminals areelectrically connected to the control circuit board 12 and the arrayboard 11 b. With this configuration, input signals supplied by thecontrol circuit board 12 are transmitted to the liquid crystal panel 11.

As illustrated in FIG. 1, the driver 21 is an LSI chip including drivecircuits. The driver 21 is configured to operate according to signalssupplied by the control circuit board 12, which is a signal source, toprocess the input signal supplied by the control circuit board 12, togenerate output signals, and to output the output signals to the displaysection AA in the liquid crystal panel 11. The driver 21 has alaterally-long rectangular shape (an elongated shape that extends alongthe short side of the liquid crystal panel 11) in a plan view. Thedriver 21 is directly connected to the non-display section NAA of thearray board 11 b of the liquid crystal panel 11, that is, mounted by thechip-on-glass (COG) mounting method. A long-side direction and ashort-side direction of the driver 21 correspond to the X-axis direction(the short-side direction of the liquid crystal panel 11) and the Y-axisdirection (the long-side direction of the liquid crystal panel 11),respectively.

Next, a connection structure of the flexible printed circuit board 13and the driver 21 to the non-display section NAA of the array board 11 bwill be described. As illustrated in FIG. 1, the edge portion of theflexible printed circuit board 13 and the driver 21 are mounted on thenon-overlapping portion of the non-display section NAA of the arrayboard 11 b not overlapping the CF board 11 a. The edge portion of theflexible printed circuit board 13 is along the short-side edge of thearray board 11 b (the X-axis direction) and the driver 21 is arranged onthe array board 11 b to have a predetermined distance from the flexibleprinted circuit board 13 and the display section AA with respect to theY-axis direction. As illustrated in FIG. 7, external connectionterminals 33 that receive supply of the input signals from the flexibleprinted circuit board 13 are formed in the mounting area for theflexible printed circuit board 13 on the array board 11 b. Panel-sideoutput terminals 34 for outputting signals to the driver 21 andpanel-side input terminals (a terminal) 35 where signals from the driver21 are input are arranged in the mounting area for the driver 21 on thearray board 11 b. Some of the external connection terminals 33 areelectrically connected to the panel-side output terminals 34 viaconnection lines 38 that are routed to cross a section between themounting area for the flexible printed circuit board 13 and the mountingarea for the driver in the non-display section NAA. As illustrated inFIG. 8, a driver-side input terminal 36 that is electrically connectedto the panel-side output terminal 34 and a driver-side output terminal37 that is electrically connected to the panel-side input terminal 35are arranged on the driver 21. The driver 21 is illustrated with adot-and-dash line in FIG. 7. In FIG. 7, a dot-and-dash line surroundingthe group of traces for displaying including the gate lines 19 and thesource lines 20 represents an outline of the display section AA and thearea outside the dot-and-dash line is the non-display section NAA.

As illustrated in FIG. 7, the external connection terminals 33, thepanel-side output terminals 34, the panel-side input terminals 35, andthe connection lines 38 are made of the first metal film 25 same as thegate lines 19 and surfaces thereof are covered with the transparentelectrode material (the first transparent electrode film 29 or thesecond transparent electrode film 31) such as ITO or ZnO similarly tothe pixel electrodes 18 or the common electrode 32. The externalconnection terminals 33, the panel-side output terminals 34, thepanel-side input terminals 35, and the connection lines 38 are formed onthe array board 11 b by patterning using a known photolithography methodat the same time when the gate lines 19 and the pixel electrodes 18 areformed by patterning in a manufacturing process of the liquid crystalpanel 11 (the array board 11 b). The external connection terminals 33include driver external connection terminals 33A and non-driver externalconnection terminals 33B. The driver external connection terminals 33Aare connected to the panel-side output terminals 34 via the connectionlines 38 and supply signals to the driver 21. The non-driver externalconnection terminals 33B supply source power to the components otherthan the driver 21, for example, gate circuit 39. The non-driverexternal connection terminals 33B include a common electrode terminal 48that is connected to an end of the common electrode connection line 47connected to the common electrode 32.

As illustrated in FIG. 8, the panel-side output terminals 34 and thepanel-side input terminals 35 are covered with an anisotropic conductivefilm ACF. The driver-side input terminals 36 of the driver 21 areelectrically connected to the panel-side output terminals 34 and thedriver-side output terminals 37 are connected to the panel-side inputterminals 35 via conductive particles ACFa included in the anisotropicconductive film ACF. As is not illustrated, the external connectionterminals 33 have a cross-sectional structure including the first metalfilm 25 and the transparent electrode material (the first transparentelectrode film 29 or the second transparent electrode film 31) similarto the panel-side output terminal 34 and the panel-side input terminal35. The external connection terminals 33 are electrically connected tothe terminals of the flexible printed circuit board 13 via theanisotropic conductive film. As illustrated in FIG. 7, the panel-sideoutput terminals 34 and the panel-side input terminals 35 are arrangedin a section of the non-display section of the array board 11 boverlapping the driver 21 in a plan view, that is, in the mounting areafor the driver 21. The panel-side output terminals 34 and the panel-sideinput terminals 35 are arranged at a predetermined interval in theY-axis direction (in an arrangement direction in which the driver 21 andthe display section AA are arranged). The panel-side output terminals 34are arranged closer to the flexible printed circuit board 13 in themounting area for the driver 21 of the array board 11 b and thepanel-side input terminals 35 are arranged closer to the display sectionAA. The panel-side output terminals 34 and the panel-side inputterminals 35 are arranged at a predetermined interval linearly in theX-axis direction, that is, along the long-side direction of the driver21 (a direction perpendicular to the arrangement direction of the driver21 and the display section AA), respectively.

As illustrated in FIG. 7, the panel-side input terminals 35 includepanel-side image input terminals 35A and panel-side control inputterminals 35B. Image signals (data signals, video signals) included inthe output signals output from the driver 21 are input to the panel-sideimage input terminals 35A. Control signals included in the outputsignals from the driver 21 are input to the panel-side control inputterminals 35B. The panel-side image input terminals 35A are arrangedfrom the right end one (one end) of the panel-side input terminal 35group toward the left side in FIG. 7 with respect to the X-axisdirection at intervals. Most of (a large number of) the terminals in thepanel-side input terminal 35 group are the panel-side image inputterminals 35A. Three panel-side control input terminals 35B are arrangedfrom the left end one (another end) of the panel-side input terminal 35group toward the right side in FIG. 7 with respect to the X-axisdirection at intervals. Some of (a small number of) the terminals in thepanel-side input terminal 35 group are the panel-side control inputterminals 35B. The panel-side image input terminals 35A and thepanel-side control input terminals 35B are arranged at a same positionwith respect to the Y-axis direction and arranged linearly along theX-axis direction.

As illustrated in FIG. 8, the driver-side input terminals 36 and thedriver-side output terminals 37 are made of metal material having goodconductivity such as gold and formed in a bump projecting from a bottomsurface of the driver 21 (a surface opposite the array board 11 b). Thedriver-side input terminals 36 and the driver-side output terminals 37are connected to a process circuit included in the driver 21. Inputsignals input from the driver-side input terminals 36 are processed viathe process circuit and the processed signals are output to thedriver-side output terminals 37. The driver-side input terminals 36 andthe driver-side output terminals 37 are arranged linearly at a certaininterval in the X-axis direction or the long-side direction of thedriver 21, respectively, similarly to the panel-side output terminals 34and the panel-side input terminals 35.

As illustrated in FIG. 7, a gate circuit 39 that is connected to thegate lines 19 of the display section AA and a test circuit 40 that isconnected to the source lines 20 are arranged in sections of thenon-display section NAA of the array board 11 b that are adjacent to theshort-side section and the long-side section of the display section AA,respectively. The gate circuit 39 and the test circuit 40 aremonolithically fabricated on the array board 11 b. The gate circuit 39and the test circuit 40 include a CG silicone thin film (thesemiconductor film 23) similar to the pixel TFT 17 as a base. Therefore,the gate circuit 39 and the test circuit 40 are formed on the arrayboard 11 b with the known photolithography method simultaneously whenthe metal films 25, 27, the insulation films 24, 26, and thesemiconductor film 23 are formed with pattering during the process ofmanufacturing the array board 11 b.

As illustrated in FIG. 7, the gate circuit 39 is next to the leftlong-side section of the display section AA and is arranged in avertically elongated rectangular area that extends in the Y-axisdirection. The gate circuit 39 is connected to the gate lines 19arranged in the display section AA and connected to gate circuit controllines 41 and gate circuit power source lines 42 arranged in thenon-display section NAA. The signals (such as clock signals) forcontrolling driving of the gate circuit 39 are supplied through the gatecircuit control lines 41, and the gate circuit control lines 41 areconnected to the gate circuit 39 at one ends thereof and to thepanel-side control input terminals 35B at another ends thereof. The gatecircuit control lines 41 are connected to gate circuit test lines 41 afor supplying test signals to the gate circuit 39, and each end of thegate circuit test lines 41 a is connected to some of the non-driverexternal connection terminals 33B. Source power is supplied to the gatecircuit 39 through the gate circuit power source lines 42. The gatecircuit power source lines 42 are connected to the gate circuit 39 atone ends thereof and connected to some of the non-driver externalconnection terminals 33B at another ends thereof. The gate circuit 39includes a scanning circuit and scan signals supplied via the gatecircuit control lines 41 are supplied to each gate line 19 at certaintiming and each gate line 19 is scanned sequentially via the scanningcircuit. Specifically, the gate lines 19 are arranged in the Y-axisdirection in the display section AA of the array board 11 b. The gatecircuit 39 scans the gate lines 19 by sequentially supplying the scansignals included in the output signals via the scanning circuit from thedriver 21 to the gate lines 19 sequentially from the upper most one tothe lowest one in FIG. 7 (FIG. 1) in the display section AA. The gatecircuit 39 may include ancillary circuits such as a level-shiftercircuit and a buffer circuit.

As illustrated in FIG. 7, the test circuit 40 is next to the lowershort-side section of the display section AA including pixels PX and isarranged in a horizontally elongated rectangular area extending in therow direction (the X-axis direction). The test circuit 40 is connectedto the source lines 20 arranged in the display section AA to test thepixel TFTs 17 included in the pixels PX and the source lines 20 in thedisplay section AA. The test circuit 40 at least includes test lines 43,test TFTs (test switching components) 44, and test terminals 45. Thetest lines extend in the X-axis direction that is perpendicular to(crosses) the Y-axis direction or the extending direction of the sourcelines 20 and test signals are transmitted through the test lines 43. Thetest TFTs 44 are connected to the test lines 43 and the source lines 20and configured to control the supply of the test signals. The testterminals 45 are connected to ends of the test lines 43 opposite fromthe test TFTs 44. On the test circuit 40, the test lines 43 are arrangedrelatively closer to the panel-side input terminals 35 and the test TFTs44 are relatively closer to the display section AA. The test lines 43 ofthe test circuit 40 according to this embodiment are made of the secondmetal film 27 and the test terminals 45 have a single-layered structureof the first metal film 25 or a multiple-layered structure of the firstmetal film 25 and the transparent electrode material (the firsttransparent electrode film 29 or the second transparent electrode film31).

As illustrated in FIG. 7, the test TFTs 44 are arranged linearly alongthe X-axis direction (the extending direction of the test lines 43) andthe number of the test TFTs 44 is equal to that of the source lines 20.Namely, each of the test TFTs supplies test signals to each of thesource lines 20 independently. As illustrated in FIG. 10, the test TFT44 includes a channel section 44 d made of the semiconductor film 23, agate electrode 44 a, a source electrode 44 b, and a drain electrode 44c. The gate electrode 44 a is disposed on and overlaps the channelsection 44 d via the gate insulation film 24. The source electrode 44 band the drain electrode 44 c are included in an upper layer of the gateelectrode 44 a via the first interlayer insulation film 26. The test TFT44 has a same configuration as the pixel TFT 17 other than that thedrain electrode 44 c is not connected to the pixel electrode 18, andwill not be described in detail. The semiconductor film 23 is formed inan island form with patterning according to the arrangement of the testTFTs 44 in the non-display section NAA. As illustrated in FIG. 7, thegate electrode 44 a of the test TFT 44 is connected to one among thetest lines 43 (a gate-side test line 43 b) for transmitting ON/OFFsignals to the test TFT 44 via a gate relay line 49. Similarly, thesource electrode 44 b of the test TFT 44 is connected to ones among thetest lines 43 (a source-side test line 43 a) for transmitting testsignals via a source relay line 50. The drain electrode 44 c of the testTFT 44 is connected to the source line 20 via a drain relay line 46. Thedrain relay line 46 is bent substantially at a right angle between thedrain electrode 44 c and a connection point connected to the source line20. The drain relay line 46 is made of the second metal film 27 similarto the drain electrode 44 c and the source line 20.

As illustrated in FIG. 9, the gate relay line 49 crosses a source-sidetest line 43 a that is connected to the source electrode 44 b, and thegate relay line 49 is made of the first metal film 25 that is includedin a lower layer than the second metal film 27 forming the source-sidetest line 43 a. According to such a configuration, the first interlayerinsulation film 26 is between the gate relay line 49 and the source-sidetest line 43 a and insulation is established therebetween. Asillustrated in FIG. 12, a contact hole CH3 is formed in a section of thefirst interlayer insulation film 26 where the gate relay line 49 and thegate-side test line 43 b are overlap and connection is established atthe overlapped section. The source relay line 50 may cross thesource-side test line 43 a and is made of the first metal film 25 thatis included in a lower layer than the second metal film 27 forming thesource-side test line 43 a. Therefore, the first interlayer insulationfilm 26 is present between the source relay line 50 and the source-sidetest line 43 a that is not connected to the source relay line 50 andinsulation is established therebetween. A contact hole is formed at asection overlapping the source relay line 50 and the source-side testline 43 a that is to be connected to the source relay line 50 toestablish connection. A cross sectional configuration thereof is similarto that of the contact hole CH3 illustrated in FIG. 12 and will not bedescribed.

As illustrated in FIG. 7, the test circuit 40 includes three test lines43 (a source-side test line 43 a and a gate-side test line 43 b) thatare parallel to each other. One of them is a gate-side test line 43 band one end thereof is connected to the gate electrode of the test TFT44 and another two of them are source-side test lines 43 a and one endsthereof are connected to the source electrodes 44 b. One of the twosource-side test lines 43 a that are to be connected to the sourceelectrodes 44 b is connected to the source line 20 connected to anodd-numbered pixel PX from an end (a left end in FIG. 7) with respect tothe X-axis direction (the extending direction of the test line 43) andthe other one is connected to the source line 20 connected to aneven-numbered pixel PX from the end. According to such a configuration,if test signals are supplied alternately to the two source-side testlines 43 a that are to be connected to the source electrodes 44 b, theodd-numbered pixels PX and the even-numbered pixels PX from the end withrespect to the X-axis direction are alternately driven according to thetest signals. Therefore, it can be tested with the test circuit 40whether short-circuit is caused between the odd-numbered pixel PX andsource line 20 from the end with respect to the X-axis direction and theeven-numbered pixel PX and source line 20. Compared to a configurationincluding three or more test lines, the area for the test circuit 40 canbe smaller and a frame area can be preferably reduced. Another end ofeach test line 43 extends outside the test circuit 40 such that the testlines 43 are connected to the test terminals 45. The test terminals 45are some of the non-driver external connection terminals 33B and thetest signals supplied from the flexible printed circuit board 13 areinput to the test terminals 45. The number of the test terminals 45 isequal to that of the test lines 43.

As illustrated in FIG. 7, terminal connection lines 51 connecting thesource lines 20 and the panel-side image input terminals 35A arearranged in the non-display section NAA of the array board 11 b. Thesignals input from the driver 21 to the panel-side image input terminals35A are transmitted to the source lines 20 via the terminal connectionlines 51 and the pixels PX connected to the source lines 20 are drivenaccording to the transmitted signals. The terminal connection lines 51are connected to any of the red pixels RPX, the green pixels GPX, andthe blue pixels BPX via the source lines 20. The terminal connectionlines 51 are arranged while overlapping the test circuit 40 via theinsulation film 52. Compared to a configuration that the terminalconnection lines do not overlap the test circuit 40 and are arrangednext to the test circuit 40 in the Y-axis direction, the area in theY-axis direction required for arranging the terminal connection lines 51and the test circuit 40 is reduced. Accordingly, the frame area of thearray board 11 b can be reduced and image resolution can be preferablyenhanced. Further, variety of design of the terminal connection lines 51and the test circuit 40 is effectively increased. The test circuit 40 isnot used when the signals are input to the panel-side image inputterminals 35A, and OFF voltage is applied to the test circuit 40 fromthe test terminals 45 such that the test TFTs 44 are always OFF.Therefore, even if the test circuit 40 is overlapped with the terminalconnection lines 51 via the flattening film 28, the signals transmittedto the terminal connection lines 51 are less likely to be influenced bynoise and display unevenness is less likely to be caused by the testcircuit 40. The terminal connection lines 51 are illustrated with brokenlines in FIG. 7.

In detail, as illustrated in FIG. 11, the terminal connection lines 51are made of the third metal film 53 that is included in an upper layerthan the first metal film 25 and the second metal film 27. Theinsulation film 52 is disposed to cover the third metal film 53.Material for the third metal film 53 is selected such that an etchantused for the patterning does not adversely affect the circuit or linesthat are already formed. Material for the insulation film 52 isappropriately selected from the same point of view.

As illustrated in FIGS. 9 and 11, the terminal connection lines 51 arearranged such that ends thereof opposite from the panel-side image inputterminal 35A side overlap the ends of the source lines 20 and theoverlapped portions are connected to each other.

As illustrated in FIG. 9, the panel-side image input terminals 35A arepositioned off from the source lines 20 in the X-axis direction (thedirection perpendicular to the extending direction of the source lines20), respectively. The terminal connection lines 51 include obliquelyextending portions 51 a that extend obliquely with respect to the Y-axisdirection (the extending direction of the source lines 20) and theobliquely extending portions 51 a overlap the test circuit 40. Indetail, the obliquely extending portions 51 a of the terminal connectionlines 51 extend a certain distance from the connection points connectedto the source lines 20 (the contact holes CH4) toward the panel-sideimage input terminals 35A. Most part of the obliquely extending portion51 a overlaps the test circuit 40. According to such a configuration,the obliquely extending portions 51 a of the terminal connection lines51 can be provided with using the arrangement area of the test circuit40. The terminal connection lines 51 disposed on the array board 11 bare arranged such that the obliquely extending portions 51 a form a planview fan shape.

As is described before, the array board (the active matrix substrate) 11b of this embodiment includes the display section (a pixel section) AA,the source lines (the pixel connection lines) 20 connected to thedisplay section AA, the test circuit 40 that is connected to the sourcelines 20 and configured to test the display section AA, the panel-sideimage input terminals (terminals) 35A that are arranged whilesandwiching the test circuit 40 with the display section AA and to whichsignals supplied to the source lines 20 are input, the terminalconnection lines 51 connecting the source lines 20 to the panel-sideimage input terminals 35A and a part of the terminal connection linebeing overlapped with the test circuit 40, and the flattening film (aninsulation film) 28 being at least between the overlapped portion of thetest circuit 40 and the terminal connection lines 51.

The signals input to the panel-side image input terminals 35A aresequentially transmitted to the terminal connection lines 51 and thesource lines 20 and supplied to the display section AA. The displaysection AA is driven based on the supplied signals. In testing thedisplay section AA during the manufacturing process, the test signalsare supplied from the test circuit 40 to the display section AA via thesource lines 20. The display section AA is driven based on the suppliedtest signals. The source lines 20 are connected to the panel-side imageinput terminals 35A via the terminal connection lines 51, and the testcircuit 40 is between the display section AA and the panel-side imageinput terminals 35A. At least a part of each terminal connection line 51overlaps the test circuit 40 via the flattening film 28. With such aconfiguration, compared to a configuration that the terminal connectionlines do not overlap the test circuit 40, the area for the terminalconnection lines 51 and the test circuit 40 is reduced. Accordingly, theframe area of the array board 11 b can be reduced and display resolutioncan be preferably enhanced. Further, the arrangement variety of theterminal connection lines 51 and the test circuit 40 can be increased.The test circuit is not used when the signals are input to thepanel-side image input terminals 35A. Therefore, the signals transmittedto the terminal connection lines 51 are not adversely affected by thenoise even with the configuration that the test circuit 40 overlaps theterminal connection lines 51 via the flattening film 28.

The panel-side image input terminals 35A are positioned off from thesource lines 20 with respect to the direction perpendicular to theextending direction of the source lines 20. The terminal connectionlines 51 include the obliquely extending portions 51 a extendingobliquely with respect to the extending direction of the source lines 20and the terminal connection lines 51 are arranged such that theobliquely extending portions 51 a overlap the test circuit 40. Accordingto such a configuration, the obliquely extending portions 51 a arearranged with using the arrangement area for the test circuit 40 and theframe area can be reduced.

The display section AA includes the pixels PX that are arranged in amatrix and the source lines 20 are connected to the respective pixelsPX. The test circuit 40 at least includes the test lines 43 and the testTFTs (test switching components) 44. The test lines 43 extend in thedirection crossing the extending direction of the source lines 20 andthe test signals are transmitted through the test lines 43. The testTFTs 44 are connected to the test lines 43 and the source lines 20 andconfigured to control the supply of the test signals. The test lines 43include ones that are connected to the source lines 20 connected to theodd-numbered pixels PX from the end of the pixels PX with respect to theextending direction of the test lines 43 and ones that are connected tothe source lines 20 connected to the even-numbered pixels PX from theend. According to such a configuration, it can be tested with the testcircuit 40 whether short-circuit is caused between the odd-numberedpixels PX and source lines 20 from the end with respect to the extendingdirection of the test lines 43 and the even-numbered pixels PX andsource lines 20. Compared to a configuration including three or moretest lines 43, the area for the test circuit 40 can be smaller and aframe area can be preferably reduced.

The liquid crystal panel (the display panel) 11 of this embodimentincludes the above-described array board 11 b and the CF board (acounter board) 11 a that is bonded to the array board 11 b. According tothe liquid crystal panel 11 having such a configuration, the array board11 b has a reduced frame area and a design property of the liquidcrystal panel 11 is improved.

Second Embodiment

A second embodiment of the present invention will be described withreference to FIG. 13. A configuration of a test circuit 140 is alteredin the second embodiment. Configurations, operations, and effectssimilar to those of the first embodiment will not be described.

As illustrated in FIG. 13, the test circuit 140 includes test lines 143that are to be connected to source electrodes 144 b of test TFTs 144 andthe same number of the test lines 143 are provided as the number ofcolors exhibited by the pixels PX. Namely, the test lines 143 includesthree test lines (source-side test lines 143 a) that are to be connectedto the source electrodes 144 b and one test line (a gate-side test line143 b) that is to be connected to the gate electrode 144 a and a totalof the test lines 143 is four. In this embodiment, the number of testlines 143 is greater than that in the first embodiment by one and thearrangement area of the test circuit 140 may be increased. However,terminal connection lines 151 are arranged while overlapping the testcircuit 140 similar to the first embodiment and therefore, thearrangement efficiency of the terminal connection lines 151 and the testcircuit 140 is improved and the frame area can be kept small.

The three source-side test lines 143 a that are to be connected to thesource electrodes 144 b include a test line to be selectively connectedto the source line 120 connected to the red pixel RPX, a test line to beselectively connected to the source line 120 connected to the greenpixel GPX, and a test line to be selectively connected to the sourceline 120 connected to the blue pixel BPX. The red pixel RPX, the greenpixel GPX, and the blue pixel BPX are sequentially driven by the testsignals by supplying the test signals sequentially to the threesource-side test lines 143 a that are to be connected to the sourceelectrodes 144 b and single color display can be performed with eachcolor of the pixels RPX, GPX, BPX. Accordingly, it can be tested whethershort-circuit is caused between the pixels RPX, GPX, BPX of each color.Further, according to the test signals supplied to the three source-sidetest lines 143 a to be connected to the source electrodes 144 b, thepixels RPX, GPX, BPX of each color can be arbitrarily driven to performmixed color display. Therefore, more various tests can be performed. Thenumber of test terminals 145 is same as that of the test lines 143.

As described before, according to this embodiment, the display sectionAA includes the coloring pixels exhibiting different colors such as thered pixels RPX, green pixels GPX, and blue pixels BPX. The source lines120 are connected to the coloring pixels of different colors of the redpixels RPX, green pixels GPX, and blue pixels BPX. The test circuit 140at least includes the test lines 143 through which the test signals aretransmitted, and the test TFTs 144 that are connected to the test lines143 and the source lines 120 to control the supply of the test signals.The number of the source-side test lines 143 a included in the testlines 143 and connected to the source lines 120 is same as the number ofcolors of the coloring pixels of red pixels RPX, green pixels GPX, andblue pixels BPX. According to such a configuration, with the testcircuit 140, the single color display may be performed by drivingselectively each of the single coloring pixels of the red pixels RPX,green pixels GPX, and blue pixels BPX or the mixed color display may beperformed by driving simultaneously the multiple coloring pixels of thered pixels RPX, green pixels GPX, and blue pixels BPX. Accordingly,various tests can be performed. In such a configuration including thesame number of source-side test lines 143 a as the number of colors ofthe coloring pixels of the red pixels RPX, green pixels GPX, and bluepixels BPX, the arrangement area of the test circuit 140 may beincreased. However, as described before, the terminal connection lines151 are arranged while overlapping the test circuit 140 and therefore,the arrangement efficiency of the terminal connection lines 151 and thetest circuit 140 is improved and the frame area can be kept small.

Third Embodiment

A third embodiment of the present invention will be described withreference to FIG. 14. In the third embodiment, a switching circuit 54 isfurther included in the first embodiment. Configurations, operations,and effects similar to those of the first embodiment will not bedescribed.

As illustrated in FIG. 14, the non-display section NAA of an array board211 b of this embodiment includes the switching circuit (a RGB switchingcircuit) 54 that is sandwiched between the display section AA and eachof a test circuit 240 and terminal connection lines 251. Namely, thetest circuit 240 and the terminal connection lines 251 are connected tosource lines 220 of the display section AA via the switching circuit 54.The switching circuit 54 has a switching function of distributing imagesignals included in output signals supplied from a driver 221 to each ofthe source lines 220.

In more detail, the switching circuit 54 is formed in a horizontallyelongated rectangular area extending in the row direction (the X-axisdirection) similar to the test circuit 240. The switching circuit 54 atleast includes selection signal lines 55 and switching TFTs 56. Theselection signal lines 55 extend in the X-axis direction that isperpendicular to (crosses) the Y-axis direction or the extendingdirection of the source lines 220 and selection signals for switchingare transmitted therethrough. The switching TFTs 56 are connected to theselection signal lines 55, the source lines 220, and the terminalconnection lines 251 and control the supply of image signals (signals).The switching TFTs 56 are arranged linearly in the X-axis direction (theextending direction of the selection signal lines 55) and the number ofthe switching TFTs 56 is same as the number of source lines 220. Namely,each of the switching TFTs 56 sends image signals to each of the sourcelines 220. The switching circuit 54 includes the switching TFTs 56 to beconnected to the source lines 220 that are connected to the red pixelsRPX, the switching TFTs 56 to be connected to the source lines 220 thatare connected to the green pixels GPX, and the switching TFTs 56 to beconnected to the source lines 220 that are connected to the blue pixelsBPX, and the switching TFTs 56 are arranged in repeated sequence alongthe X-axis direction.

The switching TFT 56 includes a channel portion formed of thesemiconductor film, the gate electrode 56 a, the source electrode 56 band the drain electrode 56 c. The gate electrode 56 a is disposed tooverlap the channel portion on an upper layer side while having the gateinsulation film therebetween. The source electrode 56 b and the drainelectrode 56 c are disposed on an upper layer side of the gate electrode56 a via the first interlayer insulation film. The switching TFT 56 hasa configuration substantially same as that of the test TFT 44 (see FIG.10) of the first embodiment. The gate electrode 56 a of the switchingTFT 56 is connected to the selection signal line 55 via the gate relayline 57. The drain electrode 56 c of the switching TFT 56 is connectedto the source line 220 via the drain relay line 59. The source electrode56 b of the switching TFT 56 is connected to the terminal connectionline 251 and the test circuit 240 via the source relay line 58. Thesource relay line 58 is routed to short-circuit the source electrode 56b of the switching TFT 56 including the drain electrode 56 c to beconnected to the source line 220 connected to the red pixel RPX, thesource electrode 56 b of the switching TFT 56 including the drainelectrode 56 c to be connected to the source line 220 connected to thegreen pixel GPX, and the source electrode 56 b of the switching TFT 56including the drain electrode 56 c to be connected to the source line220 connected to the blue pixel BPX. In other words, the source relayline 58 is branched into several lines between each source electrode 56b of the three switching TFTs 56 and the connection point (the contacthole CH4) connected to the terminal connection line 251 and the testcircuit 240. According to such a configuration, the image signalssupplied from the terminal connection line 251 and the test signalssupplied from the test circuit 240 can be distributed to each of thepixels RPX, GPX, BPX exhibiting different colors. Accordingly, thenumber of the terminal connection lines 251 and the number of the testTFTs 244 on the test circuit 240 are approximately one third(denominator is equal to the number of colors) of that in the firstembodiment. A connection structure of the gate electrode 56 a and thegate relay line 57, a connection structure of the gate relay line 57 andthe scan line 55, and a connection structure of the source electrode 56b and the source relay line 58 are similar to the respective connectionstructures of the test circuit 40 described in the first embodiment.

The selection signal lines 55 include three signal lines including asignal line connected to the gate electrode 56 a of the switching TFT 56having the drain electrode 56 c that is to be connected to the sourceline 220 connected to the red pixel RPX, a signal line connected to thegate electrode 56 a of the switching TFT 56 having the drain electrode56 c that is to be connected to the source line 220 connected to thegreen pixel GPX, and a signal line connected to the gate electrode 56 aof the switching TFT 56 having the drain electrode 56 c that is to beconnected to the source line 220 connected to the blue pixel BPX.Namely, the number of selection signal lines 55 is equal to the numberof colors exhibited by the pixels PX. If the selection signal issupplied to the selection signal line 55 in charge of the red pixel RPX,the switching TFT 56 in charge of the red pixel RPX is driven and theimage signal is supplied to the source line 220 connected to the redpixel RPX. Similarly, if the selection signal is supplied to theselection signal line 55 in charge of the green pixel GPX, the switchingTFT 56 in charge of the green pixel GPX is driven and the image signalis supplied to the source line 220 connected to the green pixel GPX. Ifthe selection signal is supplied to the selection signal line 55 incharge of the blue pixel BPX, the switching TFT 56 in charge of the bluepixel BPX is driven and the image signal is supplied to the source line220 connected to the blue pixel BPX. Each of the selection signal lines55 is connected to a corresponding one of the panel-side control inputterminals 235B and receives the selection signal from the driver 221.Each selection signal line 55 is connected to a switching circuit testline 55 a for supplying test selection signals to the switching circuit54. A terminal of the switching circuit test line 55 a is connected to acorresponding one of non-driver external connection terminals 233B. Theselection signal lines 55 are made of second metal film, which is notillustrated.

As described before, according to this embodiment, the display sectionAA includes the coloring pixels exhibiting different colors such as thered pixels RPX, green pixels GPX, and blue pixels BPX. The source lines220 are connected to the coloring pixels of different colors of the redpixels RPX, green pixels GPX, and blue pixels BPX. The switching circuit54 is sandwiched between the display section AA and the test circuit 240and connected to the source lines 220. Signals are selectively suppliedto the source lines 220 via the switching circuit 54. The terminalconnection lines 251 are connected to the source lines 220 via theswitching circuit 54. According to such a configuration, with theswitching circuit 54, the coloring pixels of each color of the redpixels RPX, green pixels GPX, and blue pixels BPX can be selectivelydriven at certain gradation by supplying signals selectively to thesource lines 220. In a configuration including such a switching circuit54, the frame area may be increased by the arrangement area of theswitching circuit 54. However, since the number of the terminalconnection lines 251 is greatly decreased and the terminal connectionlines 251 are arranged while overlapping the test circuit 240 asdescribed before, the arrangement efficiency of the terminal connectionlines 251 and the test circuit 240 is improved and the frame area can bekept small.

Fourth Embodiment

A fourth embodiment of the present invention will be described withreference to FIGS. 15 and 16. In the fourth embodiment, a commonelectrode 332 has a separated structure different from that of the firstembodiment. Configurations, operations, and effects similar to those ofthe first embodiment will not be described.

As illustrated in FIGS. 15 and 16, the common electrode 332 according tothis embodiment includes separated common electrodes 60. The separatedcommon electrodes 60 are arranged in an area ranging the pixels PX withrespect to the X-axis direction and the Y-axis direction. The separatedcommon electrodes 60 are arranged in a matrix in the X-axis directionand the Y-axis direction. With such a separated configuration of thecommon electrode 443, the same potential (a common potential) can besupplied to each of the separated common electrodes 60 and a potential(an electrostatic capacitance) of each separated common electrode 60 canbe independently detected. Therefore, the liquid crystal panel caninclude a built-in touch panel pattern and each separated commonelectrode 60 can be used as a part of the touch panel pattern. Each ofthe separated common electrodes 60 is connected to a separated commonelectrode connection line (a common electrode pixel connection line) 61separately. Namely, each of the pixels PX included in the displaysection AA is connected to the separated common electrode connectionline 61 and the source line (pixel electrode pixel connection line) 320.The separated common electrode connection line 61 is made of the secondmetal film (not illustrated) or the third metal film similar to thesource line 320. An area where the separated common electrodes 60 areformed is illustrated with a dot-and-dash line in FIG. 16.

Furthermore, as illustrated in FIG. 16, an array board 411 b of thisembodiment includes a second test circuit 62 for testing the separatedcommon electrodes 60 in the non-display section NAA. The second testcircuit 62 is between the switching circuit 354 and the test circuit340. The second test circuit is formed in a horizontally elongatedrectangular area extending in the X-axis direction. The second testcircuit 62 is connected to the separated common electrode connectionlines 61 arranged on the display section AA to test the separated commonelectrodes 60 included in the pixels PX of the display section AA. Thesecond test circuit 62 at least includes second test lines 63, secondtest TFTs 64, and second test terminals 65. The second test lines 63extend in the X-axis direction and test signals are transmittedtherethrough. The second test TFTs 64 are connected to the second testlines 63 and the second test circuit 62 and configured to control thesupply of the test signals. The second test terminals 65 are connectedto ends of the second test lines 63 opposite from the second test TFTs64. On the second test circuit 62, the second test lines 63 arerelatively closer to the panel-side input terminals 335 and the secondtest TFTs 64 are relatively closer to the display section AA. The secondtest line 63 of the second test circuit 62 according to this embodimentis made of the second metal film and the second test terminal 65 has asingle-layered structure of the first metal film, which is notillustrated, or has a multiple-layered structure of the first metal filmand the transparent electrode material (the first transparent electrodefilm or the second transparent electrode film).

As illustrated in FIG. 16, the second test TFTs 64 are arranged linearlyalong the X-axis direction and the number of the second test TFTs 64 isequal to the number of the separated common electrodes 60. Namely, thesecond test TFTs 64 supply test signals to each of the separated commonelectrodes 60 separately. The second test TFT 64 has a similarconfiguration as that of the test TFT 44 described in the firstembodiment. The gate electrodes 64 a and the source lines 64 b areconnected to the second test lines 63, and the drain electrodes 64 c areconnected to the separated common electrode connection lines 61. Thesecond test TFT 64 has a configuration similar to that of the test TFT44 of the first embodiment. The gate electrodes 64 a and the sourcelines 64 b are connected to the second test lines 63, and the drainelectrodes 64 c are connected to the separated common electrodeconnection lines 61. A connection structure connecting the second testTFT 64 to the second test line 63 and the separated common electrodeconnection line 61 is similar to the connection structure connecting thetest TFT 44 to the test line 43 and the source line 20 of the firstembodiment (refer FIGS. 11 and 12) and will not be described in detail.The second test lines 63 included in the second test circuit 62 includetest lines (second source-side test lines 63 a) connected to the gateelectrodes 64 a of the second test TFTs 64 having the source electrodes64 b connected to the separated common electrode connection lines 61connected to the odd-numbered separated common electrodes 60 from an endin the Y-axis direction (a front side in FIG. 16) and a test line (asecond gate-side test line 63 b) connected to the gate electrodes 64 aof the second test TFTs 64 having the source electrodes 64 b connectedto the separated common electrode connection lines 61 connected to theeven-numbered separated common electrodes 60 from the end. Therefore, ifthe test signals are supplied alternately to the two second source-sidetest lines 63 a to be connected to the source electrodes 64 b, theodd-numbered separated common electrodes 60 and even-numbered separatedcommon electrodes 60 from the end in the Y-axis direction are drivenalternately according to the test signals. Accordingly, it can be testedwith the second test circuit 62 whether short-circuit is caused betweenthe odd-numbered separated common electrodes 60 and the even-numberedseparated common electrodes 60 from the end in the Y-axis direction.

Furthermore, as illustrated in FIG. 16, common electrode terminalconnection lines (terminal connection lines) 66 connecting the separatedcommon electrode connection lines 61 and the panel-side input terminals335 are arranged in the non-display section NAA of the array board 311 baccording to this embodiment. Signals input to the panel-side inputterminals 335 from the driver 321 are transmitted to the separatedcommon electrode connection lines 61 via the common electrode terminalconnection lines 66, and the transmitted signals are supplied to theseparated common electrodes 60. The common electrode terminal connectionlines 66 are illustrated with broken lines in FIG. 16. Among thepanel-side input terminals 335, those connected to one ends of thecommon electrode terminal connection lines 66 are separated commonelectrode terminals (terminals) 67. The common electrode terminalconnection lines 66 are disposed to overlap the test circuit 340 and thesecond test circuit 62 via the insulation film (not illustrated) that issame as that of the first embodiment. Specifically, the common electrodeterminal connection lines 66 are made of the third metal film (notillustrated) same as that of the first embodiment and insulation isestablished between the common electrode terminal connection lines 66and the first metal film, which is not illustrated, (such as the testlines 343 and the second test lines 63) via the insulation film same asthat in the first embodiment (see FIG. 11). At least a part of thecommon electrode terminal connection line 66 overlaps the terminalconnection line 346 via the insulation film. Therefore, compared to anarrangement that the common electrode terminal connection lines are notoverlapped with the test circuit 340 and the second test circuit 62 andarranged adjacent to them in the Y-axis direction or an arrangement thatthe terminal connection lines 346 and the common electrode terminalconnection lines 66 are routed exclusively, the area in the Y-axisdirection for arranging the common electrode terminal connection lines66, the test circuit 340, and the second test circuit 62 is reduced.Accordingly, the frame area of the array board 311 b can be reduced anddisplay resolution can be enhanced preferably. Furthermore, thearrangement variety of the common electrode terminal connection lines66, the test circuit 340, and the second test circuit 62 is sufficientlyincreased. The test circuit 340 and the second test circuit 62 are notused when signals are input to the panel-side input terminals 335.Therefore, in the arrangement that the test circuit 340 and the secondtest circuit 62 are overlapped with the common electrode terminalconnection lines 66 via the insulation film, the signals transmitted tothe common electrode terminal connection lines 66 are less likely to beinfluenced by the noise.

As illustrated in FIG. 16, the separated common electrode terminals 67are positioned off from the separated common electrode connection lines61, respectively, in the X-axis direction (the direction perpendicularto the extending direction of the separated common electrode connectionlines 61). The common electrode terminal connection lines 66 includeobliquely extending portions 66 a that extend obliquely with respect tothe Y-axis direction (the extending direction of the separated commonelectrode connection lines 61). Some of the common electrode terminalconnection lines 66 include the obliquely extending portions 66 aoverlapping one of the second test circuit 62 and the test circuit 340and some of the common electrode terminal connection lines 66 includethe obliquely extending portions 66 a overlapping both of the secondtest circuit 62 and the test circuit 340. The obliquely extendingportion 66 a of the common electrode terminal connection line 66 extendsfrom a connection point connected to the separated common electrodeconnection line 61 toward the separated common electrode terminal 67 fora certain length and overlaps the second test circuit 62 or/and the testcircuit 340. According to such a configuration, the obliquely extendingportions 66 a of the common electrode terminal connection lines 66 canbe arranged while using the arrangement area of the second test circuit62 and the test circuit 340. Therefore, the common electrode terminalconnection lines 66 can be routed in a compact fan shape with more steeplines. Accordingly, the frame area can be reduced. The drain relay line346 connected to the drain electrode 344 c of the test TFT 344 isconnected to the source relay line 358 of the switching circuit 354 atone end thereof and is connected to the panel-side image input terminal335A at another end thereof.

As described before, according to this embodiment, the display sectionAA includes the pixels PX arranged in a matrix, and the pixels PX atleast include the pixel electrodes 318 to which a potential is appliedaccording to the supplied signal and the common electrode 332 to which acommon potential is applied. The common electrode 332 is arranged in anarea ranging the pixel electrodes 318 and includes the separated commonelectrodes 60 arranged in a matrix. The pixel connection lines includethe source lines 320 connected to the pixel electrodes 318 and theseparated common electrode connection lines 61 connected to therespective separated common electrodes 60. The terminal connection linesinclude at least the terminal connection lines connected to the sourcelines 320 or the terminal connection lines connected to the separatedcommon electrode connection lines 61 (the common electrode terminalconnection lines 66). According to such a configuration, the pixelelectrodes 318 are supplied with a potential according to the signalsupplied via the source lines 320, and the separated common electrodes60 included in the common electrodes 332 are supplied with a commonpotential supplied via the separated common electrode connection lines61. Display with gradation according to the potential difference betweeneach pixel electrode 318 and the common electrode 322 is performed ineach pixel PX. In a configuration that the terminal connection linesincluding the common electrode terminal connection lines 66 connected tothe separated common electrode connection lines 61, the common potentialsuppled to the panel-side image input terminals 335A is transmitted tothe separated common electrode connection lines 61 via the commonelectrode terminal connection lines 66 that are the terminal connectionlines overlapping the test circuit 340.

The terminal connection lines selectively include the common electrodeterminal connection lines 66 that are to be connected to the separatedcommon electrode connection lines 61. The test circuit 340 is connectedto the source lines 320 to test the source lines 320. The second testcircuit 62 for testing the common electrode terminal connection lines 66is provided between the test circuit 340 and the display section AA. Thecommon electrode terminal connection lines 66 connected to the separatedcommon electrode connection lines 61 are provided to overlap the secondtest circuit 62 in addition to the test circuit 340 via the insulationfilm. According to such a configuration, it can be tested with thesecond test circuit 62 whether short-circuit is caused between theadjacent separated common electrodes 60 and it can be tested with thetest circuit 340 whether short-circuit is caused between the adjacentpixel electrodes 318. In such a configuration including the second testcircuit 62, the frame area may be increased by the arrangement area forthe second test circuit 62. However, the common electrode terminalconnection lines 66, which are the terminal connection lines, aredisposed to overlap the test circuit 340 and the second test circuit 62so that the arrangement efficiency of the common electrode terminalconnection lines 66, which are the terminal connection lines, the testcircuit 340, and the second test circuit 62 is improved and the framearea can be kept small.

Other Embodiments

The present invention is not limited to the embodiments, which have beendescribed using the foregoing descriptions and the drawings. Forexample, embodiments described below are also included in the technicalscope of the present invention.

(1) Each of the above embodiments includes the terminal connection linesoverlapping the test TFTs. However, the terminal connection lines may beprovided not to overlap the test TFTs. In such a configuration, theplane arrangement of the contact hole through which the terminalconnection line is connected to the source line may be adjusted and thelength of the drain relay line connected to the drain electrode of thetest TFT and the source line may be adjusted.

(2) In each of the above embodiments, each metal film has asingle-layered structure. However, each metal film may have an alloystructure or a multiple-layered structure.

(3) Other than the above embodiments, specific material used for eachmetal film and each insulation film may be altered as appropriate.

(4) As a modified embodiment of the fourth embodiment, the switchingcircuit may not be included and the test circuit may be directlyconnected to the source lines. The switching circuit and the testcircuit may not be included.

(5) Each of the first to third embodiments includes the liquid crystalpanel that includes an FFS mode as an operation mode. However, otherliquid crystal panels are also included in the scope of the presentinvention, for example, a liquid crystal panel that includes an in-planeswitching (IPS) mode or a vertical alignment (VA) mode as an operationmode is also included in the scope of the present invention.

(6) In each of the above embodiments, the driver is directly mounted onthe array board of the liquid crystal panel with a COG technology. Thedriver may be mounted on the flexible printed circuit board and theflexible printed board may be mounted on the array board with a Chip onFilm (COF) technology.

(7) In each of the above embodiments, the gate circuit is arranged onone long-side edge of the array board. The gate circuit may be arrangedon another long-side edge of the array board. Other than that, thepresent invention may be applied to the configuration including a pairof gate circuits arranged on a pair of long-side edges of the arrayboard. In such a configuration, the gate lines arranged in the columndirection may be alternately connected to one gate circuit and the othergate circuit or one gate line may be driven at both ends thereof.

(8) Other than each of the above embodiments, the specific arrangementof the terminals, the specific routing paths of the lines, and thespecific number of the terminals and the lines may be alteredappropriately.

(9) In each of the above embodiments, the liquid crystal panel includesthe pixels of three colors including red, green, and blue. However, thepresent invention may be applied to a liquid crystal panel including thepixels of four colors including yellow in addition to red, green, andblue.

(10) In each of the above embodiments, each TFT and each circuitincludes a CG silicon thin film as the semiconductor film. Other thanthat, for example, a semiconductor film formed from amorphous silicon oroxide semiconductor may be used.

(11) Each of the above embodiments includes the liquid crystal panelhaving a vertically-long rectangular shape. However, liquid crystalpanels having a horizontally-long rectangular shape or a square shapeare also included in the scope of the present invention. Furthermore,liquid crystal panels having a circular shape or an elliptic shape arealso included in the scope of the present invention.

(12) Each of the above embodiments may further include a functionalpanel, such as a touch panel and a parallax barrier panel (a switchingliquid crystal panel), layered and attached to the liquid crystal panel.

(13) The liquid crystal display device according to the aboveembodiments includes the edge-light type backlight unit. However, theliquid crystal display device may include a direct backlight unit.

(14) The transmission type liquid crystal display devices each includingthe backlight unit, which is an external light source, are described asthe embodiments. However, reflection type liquid crystal display devicesthat use outside light to display images are also included in the scopeof the present invention. The reflection type liquid crystal displaydevices do not require backlight units. Further, semi-transmission typeliquid crystal display devices are also included in the scope of thepresent invention.

(15) Each of the above embodiments includes the TFTs as switchingcomponents of the liquid crystal display device. However, liquid crystaldisplay devices that include switching components other than TFTs (e.g.,thin film diodes (TFDs)) may be included in the scope of the presentinvention. Furthermore, black-and-white liquid crystal display devices,other than color liquid crystal display device, are also included in thescope of the present invention.

(16) The liquid crystal display devices including the liquid crystalpanels as the display panels are described as the embodiments. However,display devices that include other types of display panels (e.g., plasmadisplay panels (PDPs), organic EL panels, electrophoretic display panels(EPD), and micro electro mechanical system (MEMS) display panels) arealso included in the scope of the present invention.

EXPLANATION OF SYMBOLS

11: liquid crystal panel (display panel), 11 a: CF board (counterboard), 11 b, 211 b, 311 b, array board (active matrix substrate), 17:pixel TFT (pixel), 18, 318: pixel electrode (pixel), 20, 120, 220, 320:source line (pixel connection line, pixel electrode pixel connectionline), 32, 332: common electrode (pixel), 35, 335: panel-side inputterminal (terminal), 35A, 335A: panel-side image input terminal(terminal), 40, 140, 240, 340: test circuit, 43, 143: test line, 44,144, 244, 344: test TFT (test switching component), 51,251: terminalconnection line, 51 a: obliquely extending portion, 52: insulation film,54, 354: switching circuit, 60: separated common electrode, 61:separated common electrode connection line, 62: second test circuit, 66:common electrode terminal connection line (terminal connection line), 66a: obliquely extending portion, 67: separated common electrode terminal(terminal), AA: display section (pixel section), BPX: blue pixel(coloring pixel), GPX: green pixel (coloring pixel), PX: pixel, RPX: redpixel (coloring pixel)

1. An active matrix substrate comprising: a pixel section including aplurality of pixel electrodes and a plurality of separated commonelectrodes, the plurality of pixel electrodes being arranged in a firstdirection and a second direction intersecting the first direction, theplurality of separated common electrodes being arranged in the firstdirection and the second direction, each of the separated commonelectrode corresponding to at least two of the pixel electrodes; aplurality of source lines each of which extends in the first directionand is connected to some of the plurality of pixel electrodes; aplurality of separated common electrode connection lines each of whichextends in the first direction and is connected to corresponding one ofthe plurality of separated common electrodes; a test circuit sectionincluding a first test circuit portion being connected to the pluralityof source lines and a second test circuit portion being connected to theplurality of separated common electrode connection lines; and anexternal connection terminal section including a plurality of externalconnection terminals receiving signals to drive the pixel section,wherein the test circuit section is arranged between the pixel sectionand the external connection terminal section.
 2. The active matrixsubstrate according to claim 1, further comprising: a first test linebeing connected to the first test circuit portion; and a second testline being connected to the second test circuit portion and beingdifferent from the first test line.
 3. The active matrix substrateaccording to claim 2, further comprising: a first test terminal beingconnected to the first test line; and a second test terminal beingconnected to the second test line.
 4. The active matrix substrateaccording to claim 3, further comprising a non-display section beingarranged outside the pixel section, wherein the test circuit section,the first test line, the second test line, the first test terminal, thesecond test terminal, and the external connection terminal section arearranged in the non-display section.
 5. The active matrix substrateaccording to claim 1, wherein the first test circuit portion is formedin an elongated rectangular shape, the second test circuit portion isformed in an elongated rectangular shape, a location of the second testcircuit portion is different from that of the first test circuitportion, and a long side of the first test circuit portion is arrangedalong a long side of the second test circuit portion.
 6. The activematrix substrate according to claim 1, wherein the first test circuitportion and the second test circuit portion are arranged in the firstdirection.
 7. The active matrix substrate according to claim 6, whereinthe second test circuit portion is arranged between the pixel sectionand the first test circuit portion.
 8. The active matrix substrateaccording to claim 1, further comprising a switching circuit sectionselectively supplying signals to the plurality of source lines, whereinthe switching circuit section is arranged between the pixel section andthe test circuit section.
 9. The active matrix substrate according toclaim 1, further comprising a driver driving the pixel section, whereinthe driver is provided between the pixel section and the externalconnection terminal section.
 10. The active matrix substrate accordingto claim 9, wherein the driver is provided between the test circuitsection and the external connection terminal section.
 11. The activematrix substrate according to claim 1, further comprising a flexibleprinted circuit board including a base member having insulating propertyand flexibility, the base member having a plurality of wiring patternson its surface, wherein the external connection terminal section isconnected to the flexible printed circuit board.
 12. The active matrixsubstrate according to claim 11, further comprising a driver driving thepixel section, wherein the driver is provided on the flexible printedcircuit board.
 13. A display panel comprising: the active matrixsubstrate according to claim 1; and a counter substrate being bonded tothe active matrix substrate.